• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.2
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• pp.199-207
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• 2014

Although High-altitude electromagnetic pulse(HEMP) protection filter meets the requirements of pulsed current injection(PCI) acceptance test, the equipment under test which has low electromagnetic susceptibility level can be damaged during PCI verification test that is performed on operating condition of equipment. This paper proposed the HEMP effect analysis method using comparison of norms between residual current of HEMP filter and transient electromagnetic conducted susceptibility criteria of equipment, as an alternative method under the condition that performing PCI verification test is limited in HEMP hardened facilities. PCI acceptance test of HEMP filter, transient electromagnetic conducted susceptibility test, and PCI verification test are performed and test results are analyzed.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.3
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• pp.291-302
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• 2005

Due to the importance of the parameter in structural response, the uncertain elastic modulus was located at the center of stochastic analysis, where the response variability caused by the uncertain system parameters is pursued. However when we analyze the so-called stochastic systems, as many parameters as possible must be included in the analysis if we want to obtain the response variability that can reach a true one, even in an approximate sense. In this paper, a formulation to determine the statistical behavior of in-plane structures due to multiple uncertain material parameters, i.e., elastic modulus and Poisson's ratio, is suggested. To this end, the polynomial expansion on the coefficients of constitutive matrix is employed. In constructing the modified auto-and cross-correlation functions, use is made of the general equation for n-th moment. For the computational purpose, the infinite series of stochastic sub-stiffness matrices is truncated preserving required accuracy. To demons4rate the validity of the proposed formulation, an exemplary example is analyzed and the results are compared with those obtained by means of classical Monte Carlo simulation, which is based on the local averaging scheme.

• Korean Security Journal
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• no.29
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• pp.7-34
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• 2011

Achieving high-level technology in fields such as IT-related industry, semiconductors, mobile phones, LCD, automobile, shipbuilding, etc., Korea has become an international market leader in those fields. In results, there are the increasing numbers of technology leakage attempts in various manners. Recently, technology leakages are not limited to illegal industrial espionage, but also occur during usual corporate proceedings such as technology transfer, joint research and M&A. In fact, there was a technology leakage issue in the M&A between Ssangyong Motors of Korea and Shanghai Motors of China. Current M&A regulations of Korea are not independent laws, but are spread over various laws, such as commercial law, Capital Markets and the Financial Investment Services Act, Foreign Trade Act, etc. This paper focuses on whether the current Korean regulations regarding M&A are able to effectively restrict the leakage of major information of corporate during M&A and seeks the complements.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.6A
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• pp.1001-1011
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• 2006

It is a general agreement that exact statistical solutions can be found by a Monte Carlo technique. Due to difficulties, however, in the numerical generation of random fields, which satisfy not only the probabilistic distribution but the spectral characteristics as well, it is recognized as relatively difficult to find an exact response variability of a structural response. In this study, recognizing that the random field assumes a constant over the domain under consideration when the correlation distance tends to infinity, a semi-theoretical solution of response variability is proposed for general structures. In this procedure, the probability density function is directly used. It is particularly noteworthy that the proposed methodology provides response variability for virtually any type of probability density function, and has capability of considering correlations between multiple random variables.

• Journal of agricultural medicine and community health
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• v.34 no.1
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• pp.101-112
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• 2009

Objectives: Cattle slaughterhouse workers are known as the high risk group for the zoonoses. We surveyed the awareness of zoonoses among cattle slaughterhouse workers to suggest direction of education and public relations. Methods: We evaluated the epidemiological characteristics of zoonoses and the process of cattle slaughtering. We designed different questionnaires for the workers involved in slaughtering, the handlers of residual products, the inspectors and their assistants, and the grading testers and their assistants respectively. We visited 73 cattle slaughterhouses and 62 residual products handle houses across the country and conducted a questionnaire survey of the general characteristics and the awareness of zoonoses. The data collected was evaluated using the SPSS 17.0 statistical package. Results: The awareness rate of brucellosis, Q fever and Enterohemorrhagic Escherichia coli (EHEC) were 83.9%, 18.5%, 62.7% among cattle slaughterhouse workers. The awareness rate of zoonoses among the workers involved in slaughtering and the handlers of residual products was lower than other workers. The awareness rate of zoonoses tended to increase as the school career. In the correct awareness rate of the transmission of zoonoses, 'transmission by tick bite', 'person to person' and 'air transmission' were lower than other transmission items. The most common reason why cattle slaughterhouse workers think that it is difficult to prevent zoonoses was the ignorance of how to prevent. Conclusions: An educational program is needed for the cattle slaughterhouse workers on zoonoses especially Q fever. And publicity activities about prevention of infection are needed for high risk groups.

• The Korean Journal of Financial Management
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• v.27 no.1
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• pp.181-208
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• 2010

In July 2007, Korean government has passed "The Capital Market and Financial Investment Services Act" to further develop the capital markets and the Act was to become effective in February 2009. Using a large sample of Korean firms, we have examined (i) the effect of underwriting activities on the firm value (bond spread) comparing commercial bank and investment bank, and (ii) the determinants of the firm value changes following underwriting activities of bank. To test our goal, we collected a wide range of samples of data for bond issuing activities executed by Korean firms listed on the Korea Stock Exchange (KSE) between 2000 and 2003. Our paper is distinguished from previous studies on this subject in a way that we analyzed the effect of corporate bond underwriting activities with regard to commercial banking and investment banking. Initially, we set up a hypothesis that "Certification View" and "Conflict-of-interest View" are major driving forces behind cross-firm differences in performance following bond issuance. We find that, in general, underwriting by investment bank (securities company) brings a positive effect on the firm value (spread between bench mark rate and bond issuing rate). This result indicates that firm value has been negatively affected by the bank underwriting and provides the evidence for "Conflict-of-interest View" in Korea. Our studies have also revealed that any change in firm value following bond issuance is positively related with the firm size (total asset), operating performance, liquidity (cashflow), and equity ownership by foreign investors. Overall, our results support the view that bank underwriting activities can play an important role in determining firm value and financial strategies under "The Capital Market and Financial Investment Services Act" of 2007.

• Journal of Intelligence and Information Systems
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• v.26 no.3
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• pp.51-69
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• 2020

Now, it is a stylized fact that a small number of technology firms such as Apple, Alphabet, Microsoft, Amazon, Facebook and a few others have become larger and dominant players in an industry. Coupled with the rise of these leading firms, we have also observed that a large number of young firms have become an acquisition target in their early IPO stages. This indeed results in a sharp decline in the number of new entries in public exchanges although a series of policy reforms have been promulgated to foster competition through an increase in new entries. Given the observed industry trend in recent decades, a number of studies have reported increased concentration in most developed countries. However, it is less understood as to what caused an increase in industry concentration. In this paper, we uncover the mechanisms by which industries have become concentrated over the last decades by tracing the changes in industry concentration associated with a firm's status change in its early IPO stages. To this end, we put emphasis on the case in which firms are acquired shortly after they went public. Especially, with the transition to digital-based economies, it is imperative for incumbent firms to adapt and keep pace with new ICT and related intelligent systems. For instance, after the acquisition of a young firm equipped with AI-based solutions, an incumbent firm may better respond to a change in customer taste and preference by integrating acquired AI solutions and analytics skills into multiple business processes. Accordingly, it is not unusual for young ICT firms become an attractive acquisition target. To examine the role of M&As involved with young firms in reshaping the level of industry concentration, we identify a firm's status in early post-IPO stages over the sample periods spanning from 1990 to 2016 as follows: i) being delisted, ii) being standalone firms and iii) being acquired. According to our analysis, firms that have conducted IPO since 2000s have been acquired by incumbent firms at a relatively quicker time than those that did IPO in previous generations. We also show a greater acquisition rate for IPO firms in the ICT sector compared with their counterparts in other sectors. Our results based on multinomial logit models suggest that a large number of IPO firms have been acquired in their early post-IPO lives despite their financial soundness. Specifically, we show that IPO firms are likely to be acquired rather than be delisted due to financial distress in early IPO stages when they are more profitable, more mature or less leveraged. For those IPO firms with venture capital backup have also become an acquisition target more frequently. As a larger number of firms are acquired shortly after their IPO, our results show increased concentration. While providing limited evidence on the impact of large incumbent firms in explaining the change in industry concentration, our results show that the large firms' effect on industry concentration are pronounced in the ICT sector. This result possibly captures the current trend that a few tech giants such as Alphabet, Apple and Facebook continue to increase their market share. In addition, compared with the acquisitions of non-ICT firms, the concentration impact of IPO firms in early stages becomes larger when ICT firms are acquired as a target. Our study makes new contributions. To our best knowledge, this is one of a few studies that link a firm's post-IPO status to associated changes in industry concentration. Although some studies have addressed concentration issues, their primary focus was on market power or proprietary software. Contrast to earlier studies, we are able to uncover the mechanism by which industries have become concentrated by placing emphasis on M&As involving young IPO firms. Interestingly, the concentration impact of IPO firm acquisitions are magnified when a large incumbent firms are involved as an acquirer. This leads us to infer the underlying reasons as to why industries have become more concentrated with a favor of large firms in recent decades. Overall, our study sheds new light on the literature by providing a plausible explanation as to why industries have become concentrated.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4522-4527
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• 2014

Info-communication software contains various functions and services. A software test is the only acceptance test step. Recently, however, all development steps have become important. In particular, the software acceptance step is very high, and a study of the effective use of limited time and resources on acceptance step is needed. This study examined the efficiency of the Test Design Technique for Software Test. The proposed Test Design process was applied to the domain systems of info-communication and the degree of improvement was measured. This paper establishes Software Test design process Infrastructure based on the developed software.

• Journal of the Korea Society of Computer and Information
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• v.10 no.6 s.38
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• pp.177-186
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• 2005

In this Paper. we propose vision-based camera localization technique using 3D information which is created by mapping of DEM and mountain image. Typically, image features for localization have drawbacks, it is variable to camera viewpoint and after time information quantify increases . In this paper, we extract invariance features of geometry which is irrelevant to camera viewpoint and estimate camera extrinsic Parameter through accurate corresponding Points matching by Proposed similarity evaluation function and Graham search method we also propose 3D information creation method by using graphic theory and visual clues, The Proposed method has the three following stages; point features invariance vector extraction, 3D information creation, camera extrinsic Parameter estimation. In the experiments, we compare and analyse the proposed method with existing methods to demonstrate the superiority of the proposed methods.

• KOMUNHWA
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• no.65
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• pp.31-55
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• 2005

Ring type Bit(圓環蠻) is a specific bit that an independent Wonhwan(ring, 圓環) plays the role of the bit stopper. In three-kingdom especially 6th century A.D., It was in fashion throughout the southern part of the Korean Peninsula, The form is various accordi